I was infected with syphilis about a year ago. I had treatment at the time it was discovered, but I didn't go back for my second set of penicillin shots. I assumed it was gone, as the symptoms were gone. Later this year I find out that I still have it. So I've had another set of shots. But after recieving the shots I now have a "chancre" of some sort on the tip of my penis. My question is whether this should further concern me, or if it's possible to have a chancre appear AFTER having been treated again.

Thanks, JM

Hello JM,

Not going back to complete your treatment of syphilis is a really, really bad idea! As you have discovered, just because symptoms may subside with the first shot doesn't mean the infection is gone. By not completely treating the infection, you may have allowed it to progress to what we term secondary or tertiary syphilis.

I cannot diagnose the exact cause of your current "chancre," but it is concerning and warrants evaluation by your doctor without delay. There are other STDs associated with these types of lesions (chancroid, for instance). You will need to be screened for these and also be evaluated for the possibility of syphilis treatment failure. Also, it will be important to determine if you are continuing to put yourself at risk for STDs as well as to identify and notify anyone who may have been put at risk (unprotected sex) by your inadequate and incomplete treatment.

Good luck.

Dr. Bob